This invention relates to power modules for consumer electronic devices, and, more particularly, to a power module that is separate from the consumer electronic device and is adapted to plug into an electric power outlet and to supply a desired voltage to the consumer electronic device even during power utility brownouts and short duration power outages.
Consumer electronic devices shall be defined herein as electronic products or devices that may be used at home or in an office. These consumer electronic devices may be for example, but not limited to, telephones having memory storage, programmable digital alarm clocks, digital electronic address and information appliances, telephone answering machines, video game play stations, cable and satellite television interface boxes, smart modems, digital subscriber line (DSL) modems and routers, ethernet network hubs and switches, sprinkler system control panels, security card readers, security access keypad panels, programmable thermostats, garage door opener controllers, programmable door bell annunciators, etc.
Generic power supply modules typically power these consumer electronic devices and may be provided as a power supply interface between an electrical power outlet and the consumer electronic device. The generic power supply module may be either a linear or switching power supply that receives utility service line voltage and produces a lower voltage compatible with the consumer product being powered thereby. This lower voltage may be either alternating current (AC) or direct current (DC). The power supply module is typically adapted to plug into an electric wall outlet, either with a short power cord and plug cap or directly into the face of the electric outlet.
Generally, consumer electronic devices must be low cost and without unnecessary parts so as to stay competitive with other competing products. As such, non-volatile memory or expensive memory back-up systems are not included in order to maintain the cost competitiveness of these devices. Thus, the design of these devices assumes that utility power will be continuous. This, however, is not always the case and when there is a minor power dip (brownout) or short duration loss of power these devices typically loose information stored in volatile memory (lower in cost than non-volatile memory) such as registers and latches, static random access memory (SRAM), dynamic random access memory (DRAM) and the like. This information may be frequently dialed telephone numbers, time and alarm settings, time of day and date, network and router settings, local and cable television channels, television program schedules, billing information and user identity, temperature-time profiles, recorded messages, etc.
Small uninterruptible power supplies (UPS) have been used to protect larger and more expensive computer systems during a power brownout or unexpected power interruptions, but the computer components to be backed up must be within a power cord distance from the UPS. Typical UPS systems are disclosed in U.S. Pat. Nos. 5,751,564; 5,834,858; 5,811,895; and 5,920,129. The consumer electronic devices, however, are generally spread throughout the home or office, along with their respective power supply modules, thus making use of a common UPS for power backup purposes impractical.
What is needed is an inexpensive and effective way of preventing loss of information stored in volatile memory of a consumer electronic device during power brownout or short duration power interruptions.
The invention overcomes the above-identified problems as well as other shortcomings and deficiencies of existing technologies by providing an integrated power supply module comprising a power converter in combination with an energy storage device for powering a consumer electronic device and, in addition, preventing loss of information stored in volatile memory of the consumer electronic device during power brownout or short duration power interruptions. The power supply module, sometimes referred to as a xe2x80x9cwall-wart,xe2x80x9d is adapted to plug into an electric wall outlet, either with a short power cord and plug cap or directly into the face of the electric outlet, and connect to the consumer electronic device. The power supply module converts the voltage at the wall outlet to a voltage compatible with the consumer electronic device. The power supply module may produce either alternating current (AC) or direct current (DC), depending on the requirements of the consumer electronic device. The storage device may be a battery, a rechargeable battery or a capacitor adapted so as to provide power through the power supply module to the consumer electronic device during a power utility brownout or short duration loss of power. In addition, it is contemplated and within the scope of the invention that transient voltage protection may also be incorporated in combination with the power supply module and energy storage device.
In an embodiment of the invention the power module is encased in some form of insulated enclosure in compliance with UL(R) and/or CSA standards. The enclosure may have a two pin male connector which is integral therewith, or a power cord and plug cap (two pin male connector). The male connector is adapted to mate with contacts in the wall receptacle so as to make electrical connection thereto and also derive mechanical support therefrom. A three pin male connector which is integral therewith, and a power cord and plug cap (three pin male connector) having a safety ground connection are also contemplated herein. The three pin male connector embodiment of the invention may also be encased in a metal enclosure attached to the grounding pin of the three pin male connector.
The energy storage device is integral with the power module enclosure. The energy storage device may be located on the inside or outside of the enclosure, and may be fixed in or on, and/or removable from the enclosure. When the energy storage device is a rechargeable battery, circuits of the power converter in the power supply module may be used to recharge this rechargeable battery when utility power is present so as to maintain a full charge therein.
The power supply module may be adapted for a removable rechargeable or non-rechargeable battery or batteries and may have an appropriate battery holder or compartment that may physically retain the battery or batteries and have an electrical connector or contacts integral or associated therewith that is adapted for making electrical connection to the battery or batteries.
A battery charge or condition indicator may be included with the power supply module and may be, for example, but not limited to, a light for indicating charge state or discharge state when a non-rechargeable battery is used. A tone or pulsed tone (beep) may also be used instead of or in addition to the indicator light, for signaling a low battery charge condition. Any signaling device may be used to indicate the need to replace a non-rechargeable battery.
Battery condition status may also be transmitted to the consumer electronic device by, for example, but not limited to, an infrared transmitter, carrier current signal on the power supply wiring, a USB port, etc.
The present invention may be utilized with existing consumer electronic devices as a replacement component for an existing power supply module so as to prevent or reduce brownout and/or loss of power related mis-operation and/or failures of the consumer electronic device. Many different types and models of consumer electronic devices may be powered by the present invention, thereby improving economics of scale and reducing manufacturing costs thereof.
An advantage of the present invention is compatibility with existing and future consumer electronic devices.
Another advantage is simplification of the design and reduction of the cost of consumer electronic devices.
Still another advantage is improved operation and reduced malfunctions of consumer electronic devices.
Another advantage is low cost through mass production for use with a plurality of different consumer electronic devices.
A feature of the present invention is an energy storage device for preventing brownout and short duration loss of power in a consumer electronic device.
Another feature is a removable battery.
Still another feature is a low battery charge indicator.
Yet another feature is a rechargeable battery that is automatically charged by the power converter in the power supply module when the connected utility power is operational.
Other and further advantages and features will be apparent from the following description of presently preferred embodiments of the invention, given for the purpose of disclosure and taken in conjunction with the accompanying drawings.